WAYS TO IMPROVE ENERGY EFFICIENCY IN BUILDINGS
1 Weatherstripping of Windows and Doors
Minimise exfiltration of cool air and infiltration of warm air through leaky windows and doors by incorporating effective means of weatherstripping. Self-closing doors should also be provided where heavy traffic of people is anticipated.
2 Temperature and Humidity Setting
Ensure human comfort by setting the temperature to between 230C and 250C and the relative humidity between 55% to 65%.
3 Chilled Water Leaving Temperature
Ensure higher chiller energy efficiency by maintaining the chilled water leaving temperature at or above 70C. As a rule of thumb, the efficiency of a centrifugal chiller increases by about 2¼ % for every 10C rise in the chilled water leaving temperature.
4 Chilled Water Pipes and Air Ducts
Ensure that the insulation for the chilled water pipes and ducting system is maintained in good condition. This helps to prevent heat gain from the surroundings.
5 Chiller Condenser Tubes
Ensure that mechanical cleaning of the tubes is carried out at least once every six months. Fouling in the condenser tubes in the form of slime and scales reduces the heat transfer of the condenser tubes and thereby reducing the energy efficiency of the chiller.
6 Cooling Towers
Ensure that the cooling towers are clean to allow for maximum heat transfer so that the temperature of the water returning to the condenser is less than or equal to the ambient temperature.
7 Air-handling Unit Fan Speed
Install devices such as frequency converters to vary the fan speed. This will reduce the energy consumption of the fan motor by as much as 15%.
8 Air Filter Condition
Maintain the filter in a clean condition. This will improve the heat transfer between air and chilled water and correspondingly reduce the energy consumption.
9 Switch off Lights When Not In Use
10 Provision of Separate Switches for Peripheral Lighting
A flexible lighting system, which made use of natural lighting for the peripherals of the room, should be considered so that these peripheral lights can be switched off when not needed.
11 Install Higher Efficiency Lighting System
Use lamps with high luminous efficacy. For example, replacing incandescent bulbs with compact fluorescent lamps can reduce electricity consumption by 75% without any reduction in illumination levels.
12 Fluorescent Tube Ballasts
The ballast losses of conventional ballast and electronic ballast are 12W and 2W respectively. Hence, consider the use of electronic ballast for substantial energy savings in the lighting system.
13 Lamp Fixtures or Luminaires
Optical lamp luminaires made of aluminum, silver or multiple dielectric coatings have better light distribution characteristics. Use them to reduce electricity consumption by as much as 50% without compromising on illumination levels.
14 Integration of Lighting System With Air-Conditioning System
In open plan offices, the air-conditioning and lighting systems can be combined in such a way that the return air is extracted through the lighting luminaires. This measure ensures that lesser heat will be directed from the lights into the room.
15 Cleaning of Lights and Fixtures
Clean the lights and fixtures regularly. For best results, dust at least four times a year.
16 Use Light Colours for Walls, Floors and Ceilings
The higher surface reflectance values of light colours will help to make the most of any existing lighting system.